Errore di validazione xml del SP

In fase di validazione dell’xml ricevo il seguente errore.
Qualcuno sa darmi indicazioni su come risolverlo?
A questo link è presente l’xml:
https://test.myinsurer.it/assets/metadata/metadata_test.xml

the metadata signature MUST be valid stderr: func=xmlSecXPathDataExecute:file=xpath.c:line=246:obj=unknown:subj=xmlXPtrEval:error=5:libxml2 library function failed:expr=xpointer(id(’_19de61a5428b9fcac81fbdca1a70d59866b68d1aab’)); xml error: 0: NULL func=xmlSecXPathDataListExecute:file=xpath.c:line=330:obj=unknown:subj=xmlSecXPathDataExecute:error=1:xmlsec library function failed: func=xmlSecTransformXPathExecute:file=xpath.c:line=430:obj=xpointer:subj=xmlSecXPathDataListExecute:error=1:xmlsec library function failed: func=xmlSecTransformDefaultPushXml:file=transforms.c:line=2108:obj=xpointer:subj=xmlSecTransformExecute:error=1:xmlsec library function failed: func=xmlSecTransformCtxXmlExecute:file=transforms.c:line=1044:obj=xpointer:subj=xmlSecTransformPushXml:error=1:xmlsec library function failed: func=xmlSecTransformCtxExecute:file=transforms.c:line=1092:obj=unknown:subj=xmlSecTransformCtxXmlExecute:error=1:xmlsec library function failed: func=xmlSecDSigReferenceCtxProcessNode:file=xmldsig.c:line=1408:obj=unknown:subj=xmlSecTransformCtxExecute:error=1:xmlsec library function failed: func=xmlSecDSigCtxProcessReferences:file=xmldsig.c:line=752:obj=Reference:subj=xmlSecDSigReferenceCtxProcessNode:error=1:xmlsec library function failed: func=xmlSecDSigCtxProcessSignatureNode:file=xmldsig.c:line=517:obj=unknown:subj=xmlSecDSigCtxProcessReferences:error=1:xmlsec library function failed: func=xmlSecDSigCtxVerify:file=xmldsig.c:line=346:obj=unknown:subj=xmlSecDSigCtxProcessSignatureNode:error=1:xmlsec library function failed: Error: signature failed ERROR SignedInfo References (ok/all): 0/1 Manifests References (ok/all): 0/0 Error: failed to verify file “/tmp/tmpf1pvq6_w.xml”